Touch systems and methods utilizing customized sensors and genericized controllers

ABSTRACT

Touch sensing circuit arrangements include a touch sensor and a controller board. The touch sensor includes one or more sensing elements to generate touch-related signals responsive to a touch input to the sensor, and a memory device storing computer-executable firmware instructions for determining touch positions based on the touch-related signals. The controller board includes query logic executable by the controller board to cause the controller board to query for the computer-executable firmware instructions stored on the memory device of the touch sensor, and a processor circuit to determine touch positions by executing the firmware instructions loaded onto the generic controller board in response to the query.

CROSS REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional PatentApplication No. 61/106,898, filed Oct. 20, 2008, the disclosure of whichis incorporated by reference herein in its entirety.

The present invention relates generally to touch input systems andmethods for using, manufacturing, testing, and tracking touch systemsand components for touch systems, and in particular to touch systemsincluding generic controller boards usable across multiple differentcustomized sensors.

BACKGROUND

Touch sensing devices allow a user to conveniently and directlyinterface with electronic systems and displays in an intuitive manner.For example, a user can carry out a complicated sequence of instructionsby simply touching an on-display touch screen at a location identifiedby an icon. While the user physically interacts with the sensor portionof the touch system, controller electronics operate behind the scene toperform calculations based on received touch signals so that informationsuch as touch position may be determined. The sensor portion and thecontroller electronics portion are designed to function together suchthat the signals generated by the sensor portion in response to a touchinput may be used by the controller electronics to determine valid touchpositions. Because the sensor and controller are designed to functiontogether, replacing the sensor portion (for repair, upgrading, or otherreasons) may require replacing the controller or manually uploading newfirmware onto the controller.

SUMMARY OF THE INVENTION

In certain embodiments, the present invention provides methods ofmanufacturing touch sensing circuit arrangements, each touch sensingcircuit arrangement including a sensor to generate touch-related signalsresponsive to a touch input to the sensor, and a controller board todetermine touch positions based on the touch-related signals. Suchmethods involve producing a plurality of different sensors, each of thedifferent sensors customized by including a memory device storingcomputer-executable firmware instructions executable by the controllerboard for determining touch positions, producing a plurality ofcontroller boards, and assembling a touch sensing circuit arrangementthat includes one of the plurality of different sensors and thatincludes one of the plurality of controller boards.

In certain other embodiments, the present invention provides touchsensing circuit arrangements that include a touch sensor coupled to acontroller board, and further including computer-executable firmwareinstructions for determining touch positions. In such touch sensingcircuit arrangements, the touch sensor includes one or more sensingelements to generate touch-related signals responsive to a touch inputto the sensor, and a memory device storing the computer-executablefirmware instructions. Moreover, the controller board includes querylogic executable by the controller board to cause the controller boardto query for the computer-executable firmware instructions stored on thememory device of the touch sensor, and a processor circuit to determinetouch positions by executing the firmware instructions loaded onto thegeneric controller board in response to the query.

In certain other embodiments, the present invention provides systemswhich include touch sensing circuit arrangements includingcomputer-executable firmware instructions for determining touchpositions, and which have a controller board including a processorcircuit to determine touch positions using the computer-executablefirmware instructions, the system including one or more sensing elementsto generate touch-related signals responsive to a touch input to asurface of the sensor, the touch-related signals carried by a pluralityof signal lines, a memory device storing the computer-executablefirmware instructions, and a connector to communicatively couple thecontroller board to the signal lines and to the memory device forcommunication of the touch-related signals and the computer-executablefirmware instructions.

In certain other embodiments, the present invention provides methods fortracking parts for assembling touch sensing circuit arrangementsresponsive to specific orders, such methods including associating adifferent sensor-part number with each of a plurality of different typesof sensors, each of the different sensors including a memory devicestoring computer-executable firmware instructions specific to the typeof sensor for determining touch positions; associating a singlecontroller-part number with each of a plurality of controller boards,each controller board configured for connection to each different typeof sensor; for each different sensor-part number, managing an inventoryof the associated type of sensor based in part on sensor-specificinformation contained in the orders; and managing an inventory of thecontroller boards based in part on the total inventory for all of thedifferent sensors.

In certain other embodiments, the present invention provides testingmethods for use with a touch sensing circuit arrangement that includes acontroller board to determine touch positions based on touch-relatedsignals generated by a sensor responsive to a touch input to the sensor,the sensor including a memory device storing a configuration profileincluding computer-executable firmware instructions for determiningtouch positions. Such testing methods include assembling the touchsensing circuit arrangement by connecting the sensor to the controllerboard, loading the computer-executable firmware instructions onto thecontroller board from the sensor memory device, stimulating the touchsensor to generate test touch signals, evaluating the test touch signalsusing the computer-executable firmware instructions loaded onto thecontroller board, and verifying or modifying the configuration profilefor the sensor responsive to results of the test touch signal evaluatingstep.

In certain other embodiments, the present invention provides touchsensors that include one or more sensing elements to generatetouch-related signals responsive to a touch input to the one or moresensing elements, circuitry for communicating the touch-related signalsto a communicatively coupled device, and a memory device storingcomputer-executable firmware instructions that, when executed by thecommunicatively coupled device, cause the communicatively coupled deviceto resolve the touch-related signals into touch input positioninformation.

The above summary of the present invention is not intended to describeeach embodiment or every implementation of the present invention.Advantages and attainments, together with a more complete understandingof the invention, will become apparent and appreciated by referring tothe following detailed description and claims taken in conjunction withthe accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure may be more completely understood and appreciatedin consideration of the following detailed description of variousembodiments in connection with the accompanying drawings, in which:

FIG. 1A schematically illustrates a touch sensing circuit arrangement,along with data and process flow items, in accordance with certainembodiments of the present invention;

FIG. 1B schematically illustrates the touch sensing circuit arrangementof FIG. 1A;

FIG. 1C schematically illustrates the data and process flow items ofFIG. 1A;

FIG. 2 schematically illustrates an example electrical tail including amemory device for use with customized sensors in accordance with certainembodiments of the present invention;

FIG. 3 schematically illustrates a touch input system including a touchsensing circuit arrangement in accordance with certain embodiments ofthe present invention;

FIG. 4 schematically illustrates steps involved with producing andassembling touch sensing circuit arrangements in accordance with certainembodiments of the present invention; and

FIG. 5 schematically illustrates steps involved with tracking customizedtouch sensors and generic controller boards for providing sensingcircuit arrangements in accordance with certain embodiments of thepresent invention;

While the invention is amenable to various modifications and alternativeforms, specifics thereof have been shown by way of example in thedrawings and will be described in detail. It is to be understood,however, that the intention is not to limit the invention to theparticular embodiments described. On the contrary, the intention is tocover all modifications, equivalents, and alternatives falling withinthe scope of the invention as defined by the appended claims.

DETAILED DESCRIPTION OF EMBODIMENTS

In the following description of the illustrated embodiments, referenceis made to the accompanying drawings which form a part hereof, and inwhich is shown by way of illustration, various embodiments in which theinvention may be practiced. It is to be understood that the embodimentsmay be utilized and structural changes may be made without departingfrom the scope of the present invention.

The present invention is generally applicable to touch sensing systems,to sensor and controller components of touch sensing circuitarrangements, and to methods of manufacturing, testing, and trackingtouch sensing system components. In certain embodiments, aspects of thepresent invention are implemented through customization of sensorcomponents, allowing a generic controller boards to be used acrossmultiple types of sensors, sensor applications, and customer-specificfunctionalities. Sensor customization includes the storing of acomputer-executable configuration profile on a memory device that ismounted to the sensor. The computer-executable configuration profileincludes computer-executable instructions for determining touchpositions, and optionally includes other instructions or sensor-relateddata such as calibration factors developed for each specific sensor.

For the sake of convenience and without loss of generality, variousaspects of the present invention are described below in terms ofcontroller-executable firmware being stored on a memory device of asensor for retrieval by a controller board to determine touch positions,although it will be understood that addition data or sensorconfiguration information may also be stored on the sensor for retrievalby the controller board.

In certain embodiments, the present invention provides for touch sensingcircuit arrangements and components thereof, methods of producing andtesting touch sensing circuit arrangements and components thereof, andmethods of managing inventory of touch sensing circuit components. Suchtouch sensing circuit components include a touch sensor and a controllerboard. The touch sensor includes one or more sensing elements togenerate touch-related signals responsive to a touch input to thesensor, and a memory device storing computer-executable firmwareinstructions for determining touch positions based on the touch-relatedsignals. The controller board includes query logic executable by thecontroller board to cause the controller board to query for thecomputer-executable firmware instructions stored on the memory device ofthe touch sensor, and a processor circuit to determine touch positionsby executing the firmware instructions loaded onto the genericcontroller board in response to the query.

In accordance with certain embodiments, a generic controller platform isutilized for a variety of different customized sensors. The genericcontroller platform uses a single controller board having circuitry thatis common for each of the different customized sensors. Sensors may becustomized according to different touch sensing techniques (for example,capacitive, resistive, force, etc.) and/or according to differentcontroller-executable firmware or sensor configuration data stored alongwith the sensor. The controller-executable firmware includesinstructions for determining touch positions, and may also include otherapplication-specific or customer-specific functionalities such asinstructions for determining touch pressure, instructions fordistinguishing multiple touches or users, instructions fordistinguishing noise from touch-related signals, and so forth. Thecomputer-executable configuration profile may further include touchposition correction factors that are developed for the particular touchsensor based on a calibration routine.

In accordance with certain embodiments, storing the computer-executableconfiguration profile for each different customized sensor or sensortype along with that sensor allows genericized controller electronics tobe produced, in certain embodiments, without pre-loaded firmware fordetermining touch positions. In certain embodiments, the controllerboard includes no permanently stored firmware or instructions other thanthose used to query for and retrieve the controller-executable firmware.This can further allow production of generic controller boards eitherwithout memory devices for permanent storage of firmware, or withsmaller memory devices, thereby saving on controller board costs.Moreover, the generic controller boards may include a hardwiredinitialization routine that queries for controller-executable firmware,which can be automatically retrieved from the memory device of a sensorthat is connected to the controller board for use by a processor circuiton the controller board to determine touch position information. Thiscan reduce the burden on field technicians and touch system integratorswho might otherwise be required to manually select and load firmwareonto the controller board, thereby simplifying installation, testing andrepair operations in the field.

Aspects of the present invention also lend themselves to field serviceaimed at replacing damaged sensors and/or upgrading to sensors orfirmware with new functionalities. When a touch sensor of the presentinvention requires field replacement, field service personnel canreplace both the touch sensor and the firmware by simply replacing thetouch sensor assembly. Storing the controller-executable instructions toa memory device mounted on the sensor may also facilitate easierintroduction of new sensing technologies or functionalities that arecompatible with the existing generic controller hardware.

In certain embodiments, aspects of the present invention can alsoprovide for simplified management of touch sensor system componentinventories. Conventional inventory management of touch sensing systemcomponents has involved tracking both of the different touch sensors andof different controllers to ensure that mated sets of sensors andcontrollers are provided to customers. Aspects of the present inventionallow for the use of a single generic controller board type acrossmultiple different and customized sensors so that mated sets areproduced without requiring the tracking of different controller types.As such, separate sensor-part numbers may be assigned to each differenttype of customized sensor, with a single controller-part number beingassigned to all of the generic controller boards. Tracking of parts thusinvolves the tracking of customized sensors parts, and managing theoverall inventory of generic controller boards. Customer orders may befilled by matching sensor part numbers to order-specific information andby providing the required number of controller boards.

In certain embodiments, the touch sensor includes an electrical tail,such as a flexible cable or flex circuit, which is attached to thesensor substrate. The tail routes signal lines between the touch sensorand the controller board, which is interfaced with the sensor, in oneembodiment, via a mated connector pair, one connector being at the endof the tail and the other connector being on the controller board. Otherconnector configurations could be used. The tail can also be used toprovide an electrical connection between the controller board and thenon-volatile memory device attached to the sensor that stores thecontroller-executable firmware and optionally other configuration data.The non-volatile memory device may be a Programmable Read Only Memory(PROM) device, for example an Electrically Erasable PROM (EEPROM), orany other suitable device for permanent or long-term storage of thecontroller-executable firmware for determining touch positions. Whilethe tail may provide a convenient location to mount the non-volatilememory device, the memory device may be attached to the sensor at otherlocations such as on the periphery of the sensor surface.

The non-volatile memory device stores controller-executable firmwarethat includes instructions that are executable by a processor circuit onthe controller board to determine touch input locations fromtouch-related signals, which are received by the controller board fromthe touch sensor response to a touch input. The controller-executablefirmware may also include instructions executable to perform additionalfunctions and/or to apply correction factors to the determined touchlocation based on pre-determined correction coefficients and/or based onfeatures detected in the received touch-related signals. Such additionalfunctions may include, for example:

system diagnostic functions and touch simulation, such as disclosed inU.S. Pat. Nos. 7,362,313 and 7,236,161, and in U.S. Pub. No.20080211782, each of which is incorporated herein by reference;

distinguishing among multiple touches and/or users, such as disclosed inU.S. Pat. No. 7,254,775, and in U.S. Pub. Nos. 20060022959 and20030067447, each of which is incorporated herein by reference;

detecting or compensating for various sources of noise that may bepresent in the touch-related signals, such as disclosed in U.S. Pub.Nos. 20070034423 20060267953, which are incorporated herein byreference;

compensating for charge accumulation on the sensor, such as disclosed inU.S. Pub. No. 20080142281, which is incorporated herein by reference;

independent adjustment of each of a plurality of sensing channels, suchas disclosed in U.S. Pub. No. 20070074913, which is incorporated hereinby reference;

using multiple different touch position determination algorithms fortouch coordinate refinement and/or confirmation, such as disclosed inU.S. Pub. No. 20060279548, which is incorporated herein by reference;

detecting and tracking pre-touch signals, such as disclosed in U.S. Pub.No. 20060244733, which is incorporated herein by reference; and

correcting errors caused by sensor movement, such as disclosed in U.S.Pub. No. 20060227114, which is incorporated herein by reference.

Other functionalities that may be built into the controller-executablefirmware include palm rejection routines and parameters, controllerwake-on routines, sensor operating frequency parameters (for example,based on known or expected installation locations), rear shieldsimulation routines for use with sensors that lack a rear shieldinglayer, routines for reducing effects on touch position determinations ofhigher electrostatic discharge (ESD) immunity requirements, and soforth.

In certain embodiments, sensor-specific corrections factors may bestored on the sensor memory device as part of a sensor configurationprofile. Such correction factors may be generating during a touch sensorlinearization and/or calibration routine, which may be performed (andtested) during manufacturing, at the time of shipping, duringinstallation, or at any suitable time. Examples of sensor surfacelinearization routines for analog capacitive touch sensors include thosedisclosed in U.S. Pat. No. 6,977,646, which is incorporated herein byreference. As discussed, the correction factors may be stored with theassociated customized touch sensor along with the controller-executablefirmware.

During the latter stages of the manufacturing process for a touch sensorcomponent, the memory device for storing the controller-executablefirmware is attached to the sensor in a manner that allows connection ofthe memory device to controller electronics for query and retrieval ofthe controller-executable firmware, along with any sensor-relatedconfiguration profile. In certain embodiments, the non-volatile memorydevice is mounted on the electronic tail of the touch sensor, withelectrical leads running from the memory device to a connector at theend of the tail. This allows for a single connection that can providethe controller electronics with access to the touch-related signalsproduced by the touch sensor and the configuration information stored onthe sensor memory. Storing of the information on the non-volatile memorydevice may be performed either before or after mounting the device tothe sensor. Once attached and loaded with the controller-executablefirmware, including any correction coefficients, the sensor is fullycustomized and ready for assembly with a generic controller board, withno separate controller board tracking required.

FIG. 1A schematically shows components of a touch sensing circuitarrangement 100, and indicating certain aspects of the production,testing, assembly, and use of the components in accordance with certainembodiments. The touch sensing circuit arrangement 100 includes a touchsensor 101 which provides a touch sensitive surface 102 for interactingwith touch implements. In certain embodiments, the touch surface istransparent for positioning over a display device and viewing thedisplay therethrough. The touch surface 102 includes one or more touchsensitive elements for generating touch-related signals in response tointeractions of a touch implement with the touch surface. Thetouch-related signals are routed to an electrical tail 104 that ends ina connector 106 for interfacing with a controller board 120.Alternatively, each of multiple signal lines for carrying touch-relatedsignals may be individually routed to a connector, or individuallyconnected to the controller board.

As indicated, each sensor 101 is customized based on sensor type,firmware profile, sensor configuration profile, calibration data, and soforth. Moreover, the results of sensor selection, calibration, andtesting may be used to develop or modify the customized configurationprofile. Such calibration and testing may be repeated, for exampleduring various stages of manufacturing, storage, packaging for shipment,installation, use, and repair.

In accordance with certain embodiments, controller-executable firmwarefor use by a controller to determine touch positions from touch-relatedsignals generated by a sensor is stored on a memory device, such as thenon-volatile PROM memory device indicated in FIG. 1. Attachment of thememory device 110 to the tail 104 allows the controller-executablefirmware included in the stored configuration profile to be accessed bycircuitry on the controller board 120. It will be appreciated that othermounting locations and attachment mechanisms can be used that allowinterfacing between the memory device 110 and the controller board 120.The controller board 120 uses the controller-executable firmwareinstructions to determine touch position from the touch-related signalsgenerated by the touch sensor 101. As discussed, in addition toinstructions for determining and/or correcting touch positions, thecontroller-executable firmware may also include instructions foradditional functionality, including functionality that may be applied tomultiple sensing techniques (for example, noise reduction routines),functionality that is specific to one or more particular sensingtechnologies (for example, techniques for detecting multiple touches),and functionality that is specific to certain customers or applications(for example, ESD immunity). The configuration profile may includeparameters specific to or optimized for the particular type of sensorand/or the expected or intended environment in which the sensor will beused. The memory device 110 may also store the sensor-specificcorrection coefficients derived from calibration and/or testing.

In addition to customizing the sensors via the stored firmwareinstructions and configuration profile, sensors may be customized byincluding additional hardware on the tail, or on another portion of thesensor, to adapt or otherwise pre-condition the touch-related signalsprior to being sent to the controller board. Such additional hardwaremay be used to accommodate differences between various sensortechnologies, allowing the use of similar touch position determinationroutines across multiple sensor types, even though sensor-specificfirmware customization is employed. For example, amplifier circuits maybe used to pre-amplify the touch force-related signals of force-sensingtouch sensor prior to routing to the controller board for use with thecustomized firmware instructions stored with the sensor.

Referring again to FIG. 1A, the controller board 120 includes aconnection port 126 for interfacing with the signal lines and memorydevice of the touch sensor 101. The controller board includes thehardware circuitry for processing the touch-related signals to calculatetouch position measurements by executing the firmware instructionsstored on the memory device 110 attached to the sensor 101. For example,the controller board 120 includes a processor 122 for processingtouch-related signals by executing the firmware instructions. Thecontroller board may be pre-loaded with default firmware instructionsthat are overwritten by the new firmware instructions contained on thesensor memory device 110. Alternatively, the controller board includesno pre-loaded firmware for determining touch location, and as acost-savings measure may include no memory device for permanent storageof firmware instructions in anticipation of loading the firmwareinstructions from the sensor memory device 110 during a start-uproutine.

The circuit board 120 may be hardwired to perform an initializationroutine, which includes a query to find the firmware instructions andconfiguration data as stored on the sensor memory device 110. Thefirmware instructions and configuration data may be retrieved andlocally stored for use by the processor 122 of the controller board 120.In this way, generic controller boards can be produced, each of which isusable across the variety of sensor types and customized configurationprofiles. Such generic circuit bards executing the instructions of thefirmware retrieved from the sensor memory may also be used in furthersensor diagnostics, testing, and calibration, which may result inupdating of the configuration profile for the sensor. Such diagnostics,testing, and calibration may be performed during manufacturing, testingprior to shipment, installation, or routine maintenance.

FIG. 1B schematically shows the same sensor 101 and controller board 120components shown in FIG. 1A without the overlaid process and data flowinformation. Exemplary generic controller boards may be based on thecontroller board platform commercially available from 3M Touch Systems,Inc. under the trade designation EXII. The EXII controller boardplatform may be particularly well-suited for use with a variety of touchsensor types including analog capacitive touch sensors, analog resistivetouch sensors (including 4-wire, 5-wire, 8-wire, and so forth), force orpressuring sensitive touch sensors, and the like.

The controller board 120 may include support electronics to facilitatecommunications between the memory device 110 attached to the sensor 101and the controller electronics. The support electronics may include forexample, a multiplexer and other a logic circuitry. The multiplexermultiplexes addresses sent to the memory device and the informationloaded from the memory device onto the controller electronics. Forexample, the memory device may store multiple sets of instructions ordata at different memory addresses, including data correctioncoefficients or other sensor-specific information. The logic circuitrymay be used to provide enable signals to the memory device.

When the touch sensing circuit arrangement 100 is assembled, the tail104 routes signal lines for providing drive signals to the sensingelements of the sensor surface 102 and for receiving touch-relatedsignals from the sensor 101. For example, electrodes may be coupled tosignal-carrying lines or traces disposed on the sensor surface 102 forapplying and receiving touch signals to the sensing elements. Theelectronics located on the controller board 120 includes circuitry togenerate drive signals for the sensing elements and for calculatingtouch locations from the touch-related signals. For example, in certainembodiments, the controller 120 uses the current sensed through each ofa plurality of locations on the touch surface 102 to generate a pair ofcoordinates for an applied touch input. The controller 120 may alsocorrect for errors associated with position signals due to variations inthe sensing elements by applying correction factors, which may be storedin the touch sensor memory device 110. The controller 120 uses theexecutable instructions of the firmware retrieved from the sensor memorydevice 110 to perform the touch sensor drive, sense, and measurementfunctions so that touch positions can be determined.

The touch sensor 101 can be any suitable touch sensor that uses anysuitable touch sensing technique. Examples of touch sensing technologiesinclude analog capacitive, analog resistive, force sensing, surfaceacoustic wave, matrix capacitive, matrix resistive, inductive digitizer,infrared, vibration sensing, and so forth. In some embodiments, the samegenericized controller board and processor may be used to drive touchsensors employing different touch sensing techniques, so long as thefirmware associated with the particular touch sensor is available.

By way of brief example, a resistive touch sensor employs a flexiblemembrane positioned over a substrate. The opposing surfaces of themembrane and substrate are each coated with a transparent conductivefilm. Insulating dot spacers are interposed between the membrane and thesubstrate. When the flexible membrane is pressed by a user, theconductive film of the membrane contacts the conductive film of thesubstrate. This contact causes current to flow between the membrane andsubstrate. The controller identifies the point of contact by comparingthe current flowing from various electrodes or busbars printed on theconductive surfaces.

Unlike a resistive sensor, a capacitive touch sensor employs no movingparts. In a capacitive touch sensor, a resistive coating is depositeddirectly on an insulating substrate such as glass or a plastic film.Electrodes positioned at the corners of the substrate establish anelectrical field on the coating. The controller monitors the amount ofcurrent flowing through each of these electrodes. A user's finger, or aconductive stylus, in close enough proximity to the resistive coatingcauses capacitive coupling between the finger or stylus and the coating.This coupling causes a small amount of current to flow through thecoating and each of the electrodes. Capacitive coupling through theuser's body and ground completes the current path back to thecontroller. The controller calculates the touch coordinates from theamount of current flowing through each of these electrodes.

Force sensing sensor arrangements generate signals at multiple pointsdistributed over a touch surface based on the amount of forceexperienced at those points. For example, variable capacitance sensorsmay be placed at each of the four corners of a touch plate to sense theamount of displacement at each corner to the amount of force translatedby a touch input. The closer the touch input is to a corner, the moretranslated force, and the more displacement that is detected. Thecontroller calculates the touch coordinates from the capacitance changedetected at each of the force sensors.

FIG. 1C schematically shows the process and data flow information fromFIG. 1A without showing the sensor and controller board parts. Asindicated above, generic controller boards can be produced, therebybuilding up an inventory of generic controller boards that can be usedwith each of the variety of sensor types and with each of the customizedconfiguration profiles stored with the sensors. When the controllerboards and sensors are assembled, the controller board queries thesensor memory for the firmware and configuration profile and retrievesthe touch position determination instructions that are executable by theprocessor located on the controller board. On the sensor side, differentsensor types are selected (capacitive, resistive, force, and so on)along with firmware and customized configuration profiles. The sensorsmay be calibrated and tested to develop or modify the configurationprofiled based on sensor-specific information. The configuration profileand firmware including executable instructions for touch determinationand optionally other functionalities is stored on a non-volatile memorydevice that is attached to the sensor. As such, touch sensing circuitarrangements may be assembled from the customized sensor parts and thegeneric controller boards without necessitating tracking and mating ofcertain sensors with certain controllers.

FIG. 2 schematically shows a portion of an electrical tail 204 of atouch sensor in accordance with certain embodiments of the presentinvention. The top portion of the tail lead to the sensor (not shown),and routes the touch-related signal lines 208 from the sensor to theconnector (not shown) on the other end of the tail 204. In this case,there are five signal lines, as may be found with an analog capacitivetouch sensor having four corner signal lines and a rear shield line,with a five wire resistive touch sensor having four corner single lineson one resistive layer and a signal sink line leading to the opposingresistive layer, and other touch sensors that utilize five signal lines.The tail 204 further includes a memory device 210 attached thereto forstoring firmware and customized configuration data includinginstructions executable by the controller board. Several lines 218 leadfrom the memory device 210 to the connector (not shown) on the end ofthe tail 204 for interfacing with a controller board.

FIG. 3 schematically shows a touch input system including a touch sensor301 interfacing with a controller board 320, which in turn is connectedto a host computer 360.

In certain embodiments, a display device 370 connected to the hostcomputer 360 is viewable through the touch sensor 301 for direct userinput interaction with items displayed on the display 370.

The sensor 301 includes an electrical tail 304 for gathering and routingtouch-related signals between the sensor 301 and the controller board320. The tail 304 terminates in an interface connector 306, designed toplug into the controller board 320. A non-volatile memory device 310 ismounted on the tail 304, the memory device 310 storing firmware andcustomized configuration data including instructions for use by thecontroller board in determining touch positions from touch-relatedsignals generated by the touch sensor 301, in accordance with certainembodiments of the present invention.

The controller board 320 includes a processor circuit 322 to processtouch-related signals received from the touch sensor 301 by executingfirmware retrieved from the non-volatile memory device 310 mounted onthe electronic tail 304 of the touch sensor 301. In the embodimentshown, the controller board also includes a start-up circuit 324 thatexecutes a hardwired query routine that looks for a memory address offof the controller board from which to load firmware instruction into atemporary local memory 325, for example RAM. The processor 322 functionsto execute the firmware instructions loaded onto the temporary memory325.

FIG. 4 schematically shows steps involved in methods of certainembodiments of the present invention. In one group of steps 480, a touchsensor type and a configuration profile are selected, the firmware isstored on a non-volatile memory device, and the memory device is mountedto the sensor. The steps in grouping 480 can be performed in anysuitable order. For example, a variety of configuration profiles can bepre-selected and stored on memory devices which are inventoried based onconfiguration profile and intended sensor type. These pre-loaded memorydevices can then be attached to sensors during manufacturing or as theyare being tested or prepared for shipment. In other embodiments, thememory devices can be mounted on the sensors during manufacturing, andthe firmware and configuration profile can be stored at the latterstages of the manufacturing process or at a later time. The firmware andconfiguration profile stored on a touch sensor memory device may beoverwritten to accommodate late revision modifications, new or modifiedcustomer specifications or special functionalities, results ofadditional calibration and testing, and so forth.

Once a touch sensor prepared in accordance with the steps shown in group480, the sensor can be connected to a controller board, indicated bystep 485. As indicated by the steps in group 490, the controller boardis initialized, thereby performing a query routine, for example inresponse to being powered-up and/or being connected to the touch sensor.The query routine looks for and loads the controller-executable firmwareinstructions, optionally along with any calibration data or otherconfiguration data, from the sensor memory device onto local memory onthe controller board. The controller board is then ready to execute thecustomized instructions to determine touch input locations based ontouch-related signals received from the touch sensor.

In various embodiments, the present invention allows of much or all ofthe touch sensor system customization to be performed and stored inrelation to the sensor. As such, the same controller boards can be usedacross multiple different sensor types, sensor sizes, configurationprofiles, and custom applications. These features lend themselves tomore efficient inventory systems based on delayed customization andelimination of the need to mate specific controllers with specificsensors. Instead, a generic controller board platform can be used acrossa variety of sensor types and configuration profiles. In an exemplaryembodiment, a single controller part number is used across a pluralityof sensor types and configuration profiles, and specialized part numbersare used only for the customized sensors. This can also reduce theburden on customers, installers, and technicians who might otherwisefind the need to manually install firmware from a CD-ROM disc ordownloaded from a web site.

Delayed customization concepts are schematically indicated in FIG. 5.The steps 580 involved with manufacturing and customizing sensorcomponents may be performed separately from the steps 595 involved withmanufacturing controller boards according to a generic controllerplatform. At the time of shipping, or at another convenient time, thecustomized sensor(s) and the desired number of generic controller boardscan be selected 585 for packaging or otherwise providing to customerswithout the need to ensure that particular sensors are mated toparticular controller boards.

The foregoing description of the various embodiments of the inventionhas been presented for the purposes of illustration and description. Itis not intended to be exhaustive or to limit the invention to theprecise form disclosed. Many modifications and variations are possiblein light of the above teaching. For example, the detection methodologiesdescribed herein may be used in connection with a wide variety of touchimplements, including tethered implements and implements that house abattery or other power source. Moreover, the various processing stepscan be implemented using a variety of devices and methods includinggeneral purpose processors implementing specialized software, digitalsignal processors, programmable logic arrays, discrete logic componentsand fully-programmable and semi-programmable circuits. It is intendedthat the scope of the invention be limited not by this detaileddescription, but rather by the claims appended hereto.

1. A method of manufacturing touch sensing circuit arrangements, eachtouch sensing circuit arrangement including a sensor to generatetouch-related signals responsive to a touch input to the sensor, and acontroller board to determine touch positions based on the touch-relatedsignals, the method comprising: producing a plurality of differentsensors, each of the different sensors customized by including a memorydevice storing computer-executable firmware instructions executable bythe controller board for determining touch positions; producing aplurality of controller boards; and assembling a touch sensing circuitarrangement that includes one of the plurality of different sensors andthat includes one of the plurality of controller boards.
 2. The methodof claim 1, wherein the different sensors are customized according totouch sensing technique used by each sensor.
 3. The method of claim 1,wherein the different sensors are customized according tosensor-specific configuration data stored on the memory device.
 4. Themethod of claim 3, wherein the sensor-specific configuration dataincludes sensor calibration data developed for the sensor.
 5. The methodof claim 1, wherein sensor customization is performed by: selecting asensor type; selecting a configuration profile for the selected sensortype, the configuration profile including the firmware instructions fordetermining touch positions from touch-related signals generated by theselected sensor; storing the configuration profile on the memory device;and attaching the memory device to the selected sensor such that thememory device is accessible to the controller board upon assembly of thetouch sensing circuit arrangement.
 6. The method of claim 1, wherein theplurality of different sensors include one or more of capacitivesensors, resistive sensors, and force sensors.
 7. The method of claim 1,wherein the firmware instructions further include computer-executableinstructions for distinguishing noise from touch-related signals.
 8. Themethod of claim 1, wherein the firmware instructions further includecomputer-executable instructions for distinguishing multiplesimultaneous touch inputs.
 9. The method of claim 1, wherein thefirmware instructions further include computer-executable instructionsfor distinguishing multiple users touching the sensor.
 10. The method ofclaim 1, wherein the firmware instructions further includecomputer-executable instructions to compensate for touch-related signalerrors caused by one or more of sensor movement, charge accumulation,ESD events, or palm effects.
 11. The method of claim 1, wherein thefirmware instructions further include computer-executable instructionsfor automatic touch simulation and system diagnostics.
 12. The method ofclaim 1, wherein each of the plurality of controller boards is genericto each of the customized different sensors.
 13. A touch sensor coupledto a controller board in a touch sensing circuit arrangement, includingcomputer-executable firmware instructions for determining touchpositions, wherein the touch sensor includes one or more sensingelements to generate touch-related signals responsive to a touch inputto the sensor, and a memory device storing the computer-executablefirmware instructions, and wherein the controller board includes querylogic executable by the controller board to cause the controller boardto query for the computer-executable firmware instructions stored on thememory device of the touch sensor, and a processor circuit to determinetouch positions by executing the firmware instructions loaded onto thegeneric controller board in response to the query.
 14. The touch sensingcircuit arrangement of claim 13, wherein the memory device furtherstores sensor-specific configuration data developed for the sensor 15.The touch sensing circuit arrangement of claim 13, wherein the touchsensor further includes a touch signal adaption circuit for conditioningthe touch-related signals for use by the controller board.
 16. The touchsensing circuit arrangement of claim 15, wherein the touch signaladaption circuit includes at least one amplifier to amplify thetouch-related signals.
 17. The touch sensing circuit arrangement ofclaim 13, wherein the query logic includes controller-executableinstructions stored on the controller board.
 18. The touch sensingcircuit arrangement of claim 13, wherein the query logic is hardwired onthe controller board.
 19. In a system which includes touch sensingcircuit arrangement including computer-executable firmware instructionsfor determining touch positions, and which has a controller boardincluding a processor circuit to determine touch positions using thecomputer-executable firmware instructions, the system comprising: one ormore sensing elements to generate touch-related signals responsive to atouch input to a surface of the sensor, the touch-related signalscarried by a plurality of signal lines; a memory device storing thecomputer-executable firmware instructions; and a connector tocommunicatively couple the controller board to the signal lines and tothe memory device for communication of the touch-related signals and thecomputer-executable firmware instructions.
 20. A method of trackingparts for assembling touch sensing circuit arrangements responsive tospecific orders, comprising: associating a different sensor-part numberwith each of a plurality of different types of sensors, each of thedifferent sensors including a memory device storing computer-executablefirmware instructions specific to the type of sensor for determiningtouch positions; associating a single controller-part number with eachof a plurality of controller boards, each controller board configuredfor connection to each different type of sensor; for each differentsensor-part number, managing an inventory of the associated type ofsensor based in part on sensor-specific information contained in theorders; and managing an inventory of the controller boards based in parton the total inventory for all of the different sensors.
 21. A testingmethod for use with a touch sensing circuit arrangement that includes acontroller board to determine touch positions based on touch-relatedsignals generated by a sensor responsive to a touch input to the sensor,the sensor including a memory device storing a configuration profileincluding computer-executable firmware instructions for determiningtouch positions, the testing method comprising: assembling the touchsensing circuit arrangement by connecting the sensor to the controllerboard; loading the computer-executable firmware instructions onto thecontroller board from the sensor memory device; stimulating the touchsensor to generate test touch signals; evaluating the test touch signalsusing the computer-executable firmware instructions loaded onto thecontroller board; and verifying or modifying the configuration profilefor the sensor responsive to results of the test touch signal evaluatingstep.
 22. The testing method of claim 21, wherein the testing method isperformed as part of a manufacturing process used to produce thecustomized sensor.
 23. The testing method of claim 21, wherein thetesting method is performed as part of a pre-shipment verificationprocess.
 24. The testing method of claim 21, wherein the testing methodis performed as part of an installation process.
 25. The testing methodof claim 21, wherein the testing method is performed as part of fieldmaintenance process.
 26. The testing method of claim 21, wherein thetest touch signals are indicative of touch inputs at one or more knownlocations, and wherein evaluating the test touch signals includesdetermining one or more touch positions based on the generated testtouch signals using the computer-executable firmware instructions loadedonto the controller board, and comparing the determined one or moretouch positions to the one or more known locations.
 27. A touch sensorcomprising: one or more sensing elements to generate touch-relatedsignals responsive to a touch input to the one or more sensing elements;circuitry for communicating the touch-related signals to acommunicatively coupled device; and a memory device storingcomputer-executable firmware instructions that, when executed by thecommunicatively coupled device, cause the communicatively coupled deviceto resolve the touch-related signals into touch input positioninformation.
 28. The touch sensor of claim 27, wherein thecommunicatively coupled device is a touch sensor controller board. 29.The touch sensor of claim 28, additionally including a tail forcommunicatively coupling the touch sensor to the touch sensor controllerboard, the memory device being attached to the tail.